Is a memory leak created if a MemoryStream in .NET is not closed?

c# .net memory-leaks memorystream
Coderer picture Coderer · Oct 24, 2008 · Viewed 77.6k times · Source

I have the following code:

MemoryStream foo(){
    MemoryStream ms = new MemoryStream();
    // write stuff to ms
    return ms;
}

void bar(){
    MemoryStream ms2 = foo();
    // do stuff with ms2
    return;
}

Is there any chance that the MemoryStream that I've allocated will somehow fail to be disposed of later?

I've got a peer review insisting that I manually close this, and I can't find the information to tell if he has a valid point or not.

Answer

Jon Skeet picture Jon Skeet · Oct 24, 2008

You won't leak anything - at least in the current implementation.

Calling Dispose won't clean up the memory used by MemoryStream any faster. It will stop your stream from being viable for Read/Write calls after the call, which may or may not be useful to you.

If you're absolutely sure that you never want to move from a MemoryStream to another kind of stream, it's not going to do you any harm to not call Dispose. However, it's generally good practice partly because if you ever do change to use a different Stream, you don't want to get bitten by a hard-to-find bug because you chose the easy way out early on. (On the other hand, there's the YAGNI argument...)

The other reason to do it anyway is that a new implementation may introduce resources which would be freed on Dispose.

Related questions

Implementing IDisposable correctly

In my classes I implement IDisposable as follows: public class User : IDisposable { public int id { get; protected set; } public string name { get; protected set; } public string pass { get; protected set; } public User(int UserID) { id = UserID; } public User(string Username, …

Read More
What strategies and tools are useful for finding memory leaks in .NET?

I wrote C++ for 10 years. I encountered memory problems, but they could be fixed with a reasonable amount of effort. For the last couple of years I've been writing C#. I find I still get lots of memory problems. They're …

Read More
Memory Leak in C#

Is it ever possible in a managed system to leak memory when you make sure that all handles, things that implement IDispose are disposed? Would there be cases where some variables are left out?

Read More